C Preprocessor, Adv C

Question: What will the SWAP macro in the following program be expanded to on preprocessing? will the code compile?
#include<stdio.h> #define SWAP(a, b, c)(c t; t=a, a=b, b=t) int main() { int x=10, y=20; SWAP(x, y, int); printf("%d %d\n", x, y); return 0; }
A
It compiles

B
Compiles with an warning

C
Not compile

D
Compiles and print nothing

Note: The code won't compile since declaration of t cannot occur within parenthesis.
1. Report
Question: In which stage the following code #include<stdio.h> gets replaced by the contents of the file stdio.h
A
During editing

B
During linking

C
During execution

D
During preprocessing

Note: The preprocessor replaces the line #include <stdio.h> with the system header file of that name. More precisely, the entire text of the file 'stdio.h' replaces the #include directive.
1. Report

Question: What will the SWAP macro in the following program be expanded to on preprocessing? will the code compile?
#include<stdio.h> #define SWAP(a, b, c)(c t; t=a, a=b, b=t) int main() { int x=10, y=20; SWAP(x, y, int); printf("%d %d\n", x, y); return 0; }